Older adults rely heavily on the automobile to maintain their mobility, and thus driving is tied to quality of life, personal independence, and self esteem. Cognitive impairment has been identified in prior work as a risk factor for unsafe driving and crash involvement in older adults. While most experts agree that driving is unsafe and therefore unwarranted in the moderate to severe stages of AD, there is a great deal of controversy about whether those with the mild form of this condition should be behind the wheel. Rather than stereotyping older drivers with presumed mild 'AD as having a high crash risk, an increasing number of experts are arguing that the functional evaluation of driving skills is the only fair way to decide for or against licensure in an individual driver, because age or medical diagnosis alone have proven to be unreliable as criteria. In this project, we propose a prospective study to examine the relationship between cognitive impairment and driving performance in older adults with mild Alzheimer's disease (AD) and in age-matched controls who do not have AD. Subjects will be made available to the project through the ADRC Clinical Core. Cognitive abilities will be assessed by a comprehensive battery of tests covering cognitive and other functional domains believed to be important to safe driving. These tests will be carried out by the ADRC Neuropsychology Core, and supplemented by additional tests on the day of driving assessment. Driving performance will be assessed in a driving simulator which provides several measures of driving ability under various task demands. The driving simulator facility is already in place at UAB and is made available as a research resource by the NIA-funded Roybal Center for Research in Applied Gerontology. Any associations found between cognitive impairment and driving simulator performance will be adjusted for potential confounders such as age, vision impairment, and other chronic medical and functional problems known to impact driving ability in older adults. The major goal of this project is determine how cognitive impairment in persons with AD is related to impaired driving performance, so that a functional test battery can be ultimately developed to screen older persons with AD for fitness to drive.